Researches have so far been undertaken to separate from mixed sounds a particular sound such as a voice or a music sound included in the mixed sounds. For example, a sound recognition system has been known that assumes its input sound to be a speech or voices. And, insofar as image or image processing is concerned, a system has been known which in educing an object assumes its color, shape and/or movement to characterize it.
There has so far been no sound recognition system, however, that associates sound recognition with image processing. On the other hand, the system assuming a speech or voices is only effectuated when a microphone is near the mouth or where there is no other sound source.
Further, while there is a system proposed to separate based on a harmonic structure, a particular sound signal from those from a plurality of sound sources and then to find the direction in which its sound source is located, the accuracy with which the direction of the sound source can be found thereby is as rough as ±10°, and it is not possible to separate the sound source if it lies close to an adjacent sound source or sources.
There has also been proposed a method that uses a plurality of sound collecting microphones the same in number as sound source and, based on sound information from the various sound collecting microphones, to identify a particular sound source. While this method is designed to identify the intensity of a sound and the location of its source, its frequency information comes to spread about the axis defining the direction in which the sound source is located, thereby making it difficult to finely identify the sound source. Further, while this method makes it possible to increase the rate of recognition of a sound source, the requirement for sound collecting microphones the same in number as sound sources existing independently of one another makes the method costly.
Aimed to obviate the difficulties entailed in the prior art as described above, the present invention has for its first object to provide a sound source identifying apparatus that is capable of identifying an object as a source of a sound in mixed sounds in terms of its location with greater accuracy by using both information as to the sound and information as to the sound source as an image thereof and using information as to that position to separate the sound from the mixed sounds with due accuracy.
The present invention further has for its second object to provide a sound source identifying method that is capable of identifying an object as a source of a sound in mixed sounds in terms of its location with greater accuracy by using both information as to the sound and information as to the sound source as an image thereof and using information as to that position to separate the sound from the mixed sounds with due accuracy.